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Re: Interface type

> Let me put it another way - given an interface name, can I find out
> if it represents a physical device?

"You can't".

Seriously, the question doesn't even really make all that much sense.
What exactly does it mean to "represent a physical device"?  Does a
vlan interface represent a physical device?  Does it depend on what its
vlanif setting is?  What about an aggregator device?  What about tap0
if it's being used with a suitable userland program to speak to, let's
say, a parallel-port ethernet device via /dev/lpt0?  What about tap0 if
it's an OpenVPN tunnel?  What about a Xen xvif interface?  A Xen xennet

Depending on why you care, and in some cases other things not mentioned
above, the answers to each of those questions will vary.  Network
interfaces as userland sees them are software fictions; the extent to
which they are backed by hardware is full of grey areas.

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